Cylindrical jack for drill holes and combination thereof with a recording device



Feb 1965 J. ANTOINE-AUGUSTE TALOBRE 3, 8

CYLINDRICAL JACK FOR DRILL HOLES AND COMBINATION THEREOF WITH ARECORDING DEVICE Filed Dec 1 1962 2 Sheets-Sheet 1 2oFlG.l

JOSEPH AN TOINE-AUGUSTE TALOBRE R W IT w m WW- 1 9 2 J .1 MS. //W, I b l8 A 2 4 3 o III I 8 4' ATTORNEYS 1966 J. ANTOINE-AUGUSTE TAL RE3,234,788

CYLINDRICAL JACK FOR DRILL HOLES A COMBINATION THEREOF WITH A RECORDINGDEVICE Filed Dec. 17, 1952 2 Sheets-Sheet 2 INV ENI OR J OSEPH ANTQIN EAUGUSTE TALOBR E ATTORNEYS United States Patent 8 Claims. (cl. 73-152This invention relates to a cylindrical jack for drill holes designedfor geotechnical measurements. A cylindrical jack is of the greatestutility for checking the quality of a rock, and particularly that of damabutments.

Various types of apparatus have been resorted to heretofore forconducting tests of this order, but they have the drawback either ofbeing too heavy, requiring the prior excavating of an access gallery tothe zone to be explored (such galleries being costly and alsodetrimental to the stability of the terrain to be explored), of callingfor the execution of relatively large bore holes, of preventingexploration to great depths, or of being accurately applicable only toloose ground.

The cylindrical jack of this invention allows in particular forovercoming these drawbacks. This invention accordingly has for itsobject to provide a cylindrical jack adapted to be slipped into theusual types of bore holes, such as those necessary for geological surveyor those used for geotechnical survey, or into bore holes speciallyprepared for strength tests and through which the desired point can bereached.

It is another object of the invention to provide a cylindrical jackusable for computing rock characteristics, so as to determine the degreeof safety offered by the rock.

It is a further object of the invention to provide a cylindrical jackadapted to furnish a number of figures sufficient to safely characterizethe strength of a rock, and to do so both economically and rapidly.

It is also an object of the invention to provide a sturdy yet compactapparatus, by using a cylindrical jack which is preferably made ofmetal.

It is another object of this invention to provide an apparatus whichallows for measuring such rock characteristics as the modulus ofelasticity, the cohesion, the angle of internal friction, the internalvertical compression of the rock, and the like, and which utilizes aflat metal jack set under pressure by a virtually non-compressibleliquid that does not attack metal and wherein the volume of liquid usedis reduced to a minimum, thereby eliminating for all practical purposesthe usual causes of error as well as the corrections normally made toallow for the compressibility of liquids and for their thermalexpansion.

It is yet another object of the invention to provide an apparatus of thetype cited hereinbefore, wherein said apparatus is filled with liquidonce and for all in a workshop and can be lowered into a drill holewithout being emptied, yet without being in danger of becoming jammed inthe drill hole.

It is still another object of the invention to provide an apparatuscomprising a cylindrical jack of the aforementioned type combined withan apparatus located above ground which automatically records the testdata.

It is the object of the present invention to provide an apparatus formeasuring rock characteristics, which is characterized by its mobility,convenience and high speed operation.

A cylindrical jack according to the invention can be built to an outerdiameter of about three inches and can be utilized very effectively inrock, since it enables very high pressures to be applied, for instanceof the order of 200 kg./cm. it also enables zones as deep, say, as 100meters, to be explored.

3,234,788 Patented Feb. 15, 1966 Other objects of the invention,together with other advantages, will become apparent from the followingdescription with reference to the accompanying drawing, which is givenby way of example and not of limitation, and in which:

FIGURE 1 is a diagrammatic side elevation view of a cylindrical jackembodying the invention;

FIGURE 2 is a longitudinal sectional view thereof;

FIGURE 3 is a cross-section taken through the line IIIIII of FIGURE 2;

FIGURE 4 is a schematic perspective view of a recording device connectedto the cylindrical jack of FIGURES 1 to 3.

The apparatus according to the invention basically comprises a generallycylindrical shaped cylindrical jack proper, the nominal diameter ofwhich is three inches, say, designed to be lowered into a drill hole ofslightly larger diameter and adapted to exert a high radial pressureagainst the sides of the bore hole, and a device for reading andpreferably recording the deformations of the walls of the bore hole.This latter device linked to the cylindrical jack is installed in theopen air and its function is to render visible and preferably record, ingraphical form, such displacements of the wall of the drill hole as areoccasioned by the pressure exerted by the cylindrical jack.

The cylindrical jack is itself divided into two parts (see FIGURES 1through 3). It comprises a pressure applying member generally designatedby the reference numeral 1 and positioned in the lower portion of anenclosure 2 containing equipment for converting the displacementdetected into electrical or pneumatic signals or into further mechanicalmotions calculated to actuate the recording devices of the apparatusinstalled in the open air.

The pressure applying member 1 is composed of a certain number ofsegments or staves 3 made of some hard material such as wood or metal,which together substantially form a hollow cylinder. The number ofstaves is preferably even and greater than two, six for instance. Saidstaves are separated by pressure generating members (the number of whichis consequently equal to the number of staves), such as flat jacks orbellows 4, inflated to an equal but variable pressure. The flat jacks 4can be made of metal or not, but their walls are preferably thin, beingmade of stainless metal possibly strengthened by a network of thin,very-heavy-duty steel wires. The deformation that can be withstood bythese special jacks thus greatly exceeds normal service requirements.The bellows or flat jacks are set under pressure by a virtuallynon-compressible liquid that will not attack the metal used, inaccordance with a flow diagram to be described hereinafter.

As illustrated in FIGURE 3, said bellows 4 comprise a flat portionbordered on each side by rounded portions, one of which is in contactwith two successive staves in the internal space left by the severalstaves, and the other lodged in recesses which are formed at the outerjoint between two staves to prevent the bellows from projectingexternally from the cylindrical contour formed by said staves. Thelength over which the pressure is appliedwhich is also the length of theflat bellows 4-is equal, for example, to five times the diameter.

The staves 3 and the bellows 4 are retained by upper and lower springs 5and 5' respectively. Said springs are calibrated springs which preventthe cylindrical jack from inflating under the weight of the column ofliquid when it is lowered into a drill hole. The staves are drilled withlongitudinal bores 6 inside which are disposed tie-rods 7 having studlike threaded extremities. Said tie-rods confine the staves between aterminal piece 8 and a further piece 9 forming part of the enclosure 2.Suitable clearance is provided between the tie-rods and the bores toallow for radial deformations of the staves.

The device for detecting radial deformations of the staves comprises,for example, horizontal rods 10, each of which is rigidly connected tothe middle portion of a stave. Said rods extend through the staves andtheir extremities a are rigid with the outer stave faces in contact withthe sides of the drill hole into which the cylindrical jack is lowered.With an even number of staves, the horizontal rods can be associated indiametrically opposed pairs. The inner extremities 10b of two opposedrods co-operate with a beam-lever 11 supported by a vertical shaft 12,in such manner that the radial displacements sustained by the staves incontact with the wall of the drill-hole, when pressure is applied by thebellows 4, are converted into rotations of the vertical shafts 12. Thetie-rods 7 penetrate into enclosure 2 via flexible and leakproof seals13 (see FIG- URE 2).

Inside said enclosure 2, the very small rotations of the shafts 12 areamplified by a multiplier 15 and transmitted in the form of rotationseither to electric telemetering means 16, or to a mechanicaltransmitting device such as a flexible connection.

The flexible connection or the electric output leads from the device 16pass through a duct 17 which extends through the top of enclosure 2 viaa leakproof union 18. A flexible line 19 conveys the oil or otherconvenient fluid under pressure to the flat bellows 4. A flexible sheath20 protects both the flexible line 19 and the flexible connection orelectric lead means. The oil line 19 is connected to a conventionalpressurizing pump installed above ground. Said pump is capable, say, ofimparting a head of about 300 kg./cm. to the oil.

A cable 21 is provided to raise the apparatus to the surface, even inthe event of its becoming jammed in the drill hole.

The flexible connections or electrical leads are connected to a surfaceapparatus which gives readings of the values of the radial deformationsof the drill hole. Said apparatus should preferably be a recordingapparatus, similar for example to that illustrated in FIG- URE 4.

The device for recording the deformations is contained in a casing 23.The apparatus is of the transportable type and its function is to plotautomatic graphs of diametrical deformations of the drill hole versuspressure. To this end, it comprises recording cylinders 24 equal innumber -to the number of shafts 12, each of which is pivoted in responseto the action of two rods 10. Fresh sheets of paper are rolled onto saidcylinders for each experiment. The graphs are plotted by styluses 24'which are displaced parallel to the cylinder axes through amountsproportional to the pressure transmitted to the flat bellows 4 of thecylindrical jacks. Said styluses are operated by bellows device 25 whichare connected to flexible line 19 between the pressurizing pump and thecylindrical jacks. In turn, each cylinder 24 revolves about its axis byan amount proportional to the angular displacement of the correspondingshaft 12 and is controlled by one of the strain gages formed by twoopposed rods 10. The cylinder can be rotated either by mechanical meansor by an electric remote control device 26. The link between component26 and the transmitter 16 contained in enclosure 2 is achieved throughthe wiring running through duct 17.

The casing 23 further contains a chronometer 27 complete with bell, forfacilitating the conduct of the pressurizing operations in accordancewith a scheduled program. It is further equipped with accurate pressuregages 28 and 29 to indicate the pressure in flexible line 19. Saidcasing 23 is preferably supported on a table equipped with adjustablelegs 30.

Thus, in operation, when the cylindrical jack staves are deformed underthe action of the pressurizing members 4 and exert pressure against thesides of the drill hole, this results, on the one hand, in styluses 24mov ing parallel with the axes of cylinders 24 and, on the other, insaid cylinders revolving to an extent dependent upon the deformationssustained by the walls of the drill hole. Graphs are consequentlyobtained directly, in which the wall deformations are plotted againstthe pressure exerted and form which it is possible to determine variousgeotechnical characteristics of the terrain in which the drill hole ismade.

It will be seen therefore that the apparatus can be lowered into a drillhole, moved, set under pressure, relieved of pressure, etc., as desired,merely by operating a few levers. It can be used anywhere, remote fromany water point or electric line. It requires no supervision other thanmonitoring the pressures to be varied in accordance with a presetprogram and the depths at which the cylindrical jack is to be fixed. Allthe other operations are performed automatically. In addition, nocomplex operation is necessary for setting up the apparatus. It can beset under pressure at heightened speed and no special operation isrequired to record the results, it being suflicient to change therecording drurn at the appropriate time.

By reason of this mobility, convenience and rapidity, great time savingsare insured and the operating cost is considerably reduced. By virtue ofthe time saving effected, the measurements can be virtually multipliedas desired, at any depth, while the low cost of the tests permits alarge number of measurements-a hundred or so, for exampleto be made atany given site. The measurements can even be renewed, if need be,without the resulting expenditure being unduly increased. Thus all therequirements are ideally met to permit thorough and effectiveexploration of the rock sites studied, and hence to insure the successof such projects under 0ptimum conditions of safety, quality, time andcost.

It will be evident to those skilled in the art that many changes may bemade to the specific embodiments herein before described, withoutdeparting from the spirit or scope of the invention.

By way of example, it will be manifest that the figure of six cited byway of example for the number of staves was given chiefly forillustrative purposes. However, as stated precedingly, it is preferableto have an even number of segments, greater than two, in order to permita plurality of simultaneous and independent diameter meas urements, bycumulating the spacings of two segments located symmetrically withrespect to the cylindrical jack axis.

What I claim is:

1. A cylindrical jack for bore holes, comprising a pressure applyingmember consisting of segments numbering more than two and disposed tosubstantially form a hollow cylinder, pressurizing means positionedbetween adjacent segments for setting the same under variable pressure,detecting means disposed within said cylinder for detecting diametricaldisplacements of said segments when said pressurizing means areoperative, and means to convey a signal related to said displacement toa remote display device.

2. A cylindrical jack according to claim 1, wherein said segments areeven in number.

3. A cylindrical jack according to claim 1, wherein said pressurizingmeans are flat metallic bellows which are inflatable under the action ofa liquid under pressure.

4. A cylindrical jack according to claim 1, wherein said detecting meanscomprise members which convert the radial displacements of said segmentsinto rotations of a shaft disposed axially within said cylinder.

5. A cylindrical jack according to claim 4, wherein said memberscomprise, in respect of each pair of segments, a pair of opposed rodshaving one of their extremities respectively rigid with the outer facesof said pair of segments, and a beam-"lever supported on said axialshaft and rotated by the other extremities of said pair of rods.

6. A cylindrical jack according to claim 1, wherein said signalconveying means comprises an upper substantially cylindrical enclosurefrom which said pressure applying member is dependent, and apparatusdisposed within said enclosure for amplifying the values detected bysaid detecting means and for transmitting said signal related to saidvalues to the surface through a flexible connection.

7. An apparatus for measuring the rock characteristics in a drill hole,comprising, in combination, a cylindrical jack adapted to be introducedinto said drill hole and comprising a lower pressure-applying membercomposed of a plurality of segments numbering more than two and arrangedto substantially form a hollow cylinder, deformable pressurizing meansdisposed between adjacent segments for setting the same under variablepressure in response to the action of a pressurized liquid, detectingmeans disposed within said cylinder for detecting the displacements ofsaid segments when said pressurizing means are energized by said liquid,a substantially cylindrical upper enclosure from which said lowerpressure-applying member is dependent, amplification means disposedwithin said enclosure, a transportable recording apparatus set up in theopen air and connected to said amplification means through a flexibleconnection, and means connected to said deformable pressuring means forsupply ing liquid under pressure.

8. An apparatus according to claim 7, wherein said deformablepressurizing means for setting said segments under pressure are flatmetallic bellows which are inflatable under the action of said liquid.

References Cited by the Examiner UNITED STATES PATENTS 2,150,070 3/1939Kregecz 33178 2,638,168 5/1953 Parks 166-187 X 2,957,341 10/1960 Menard7384 RICHARD C. QUEISSER, Primary Examiner.

ROBERT L. EVANS, Examiner.

1. A CYLINDRICAL JACK FOR BORE HOLES, COMPRISING A PRESSURE APPLYING MEMBER CONSISTING OF SEGMENT NUMBERING MORE THAN TWO AND DISPOSED TO SUBSTANTIALLY FORM A HOLLOW CYLINDER, PRESSURIZING MEANS POSITIONED BETWEEN ADJACENT SEGMENTS FOR SETTING THE SAME UNDER VARIABLE PRESSURE, DETECTING MEANS DISPOSED WITHIN SAID CYLINDER FOR DETECTING DIAMETRICAL DISPLACEMENTS OF SAID SEGMENTS WHEN SAID PRESSURIZING MEANS ARE OPERATIVE, AND MEANS TO CONVEY A SIGNAL RELATED TO SAID DISPLACEMENT TO A REMOTE DISPLAY DEVICE. 